Toyota hints at a baby sister for Prius as it gets set to reveal a new hybrid

FRESH from announcing this week that it will start production of a plug-in version of its hybrid Prius in 2011, Toyota has released teaser photos of another dedicated hybrid concept vehicle that it plans to unveil at the North American International Auto Show in January.

The Japanese giant is keeping other details of the car under wraps, saying only that all will be revealed at a press conference at Detroit’s Cobo Hall on January 11.

The images of what appears to be a small runabout with a stubby bonnet triggered an avalanche of media speculation about the origins, size, architecture and technology of the new car, but comparisons of what little can be seen of the vehicle with existing Toyota models, including the Prius, iQ mini car and Yaris light car, seem to indicate this might indeed be an all-new vehicle – a baby sister to Prius.

Compact headlights are clustered just in front of the A-pillars, in a similar location to those on the iQ mini now on sale in Europe and the UK, but iQ is not a “dedicated hybrid”, being sold with petrol three- and four-cylinder engines, with an electric powertrain in the pipeline.

In the US, the Detroit News quotes analysts as saying the car is a new concept for a vehicle that Toyota plans to put into production in two years.

The shortness of the bonnet hints that the car is unlikely to accommodate a substantial Prius-style petrol-electric Hybrid Synergy Drive system, suggesting Toyota might be set to break new ground on a new-generation, more compact drive system for city-car applications.

Logic says the car will be a plug-in hybrid, as Toyota seems to be moving that way in line with other manufacturers. Just this week, Toyota confirmed that the next iteration of Prius in 2011 would be a plug-in, allowing the batteries to be charged from mains power for trips of up to 20km on battery power before the petrol engine has to kick in.

All current Toyota hybrids – including the Camry Hybrid that has just gone into production in Toyota's Australian plant ahead of its February launch – have relied on the petrol engine and regenerative braking to charge the batteries.

The new car to be shown at Detroit could also be expected to have the latest lithium-ion batteries, which Toyota is about to field-test in 600 specially built plug-in hybrid Prius prototypes around the world, including in Australia.

Thus far, Toyota hybrids have been equipped with nickel-metal hydride batteries, which the company regards as tried and true technology.

Most other manufacturers have already announced they are stepping up to lithium-ion, due to its superior qualities for plug-in applications.

Toyota has promised that it will produce variations of the Prius – a wagon, for example – over time, but the Detroit vehicle does not appear to be one of those.